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The math we use, made available to you.

Professional estimation tools for electrical contractors and designers. Calculate critical specifications for low-voltage installations. Formulas align with IEC/BS 7671.

Preliminary Use Only

Calculators provide estimates under standard conditions. Verify specifications against current IEC/BS 7671 regulations with an NPE design engineer.

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Cable Sizing

IEC 60364 Copper Conductor

Determine minimum conductor size based on continuous currents, phase connections, installation methods, and thermal grouping factors.

⚡ Output — Calculated Results

Adjusted current

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Min Conductor

—

Breaker size

—

⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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kVA ↔ Amps

Bidirectional Converter

Convert electrical load values between kVA and Line Amps across single phase, split phase, or polyphase industrial supplies.

⚡ Output — Calculated Results

Equivalent Amps

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Active Power

—

Reactive Load

—

⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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Capacitor Bank Sizing

Power Factor Correction

Calculate the required reactive power (kVAR) steps to stabilize system phase lag, raise power factor, and eliminate reactive load penalties.

⚡ Output — Calculated Results

Required kVAR

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Standard Bank

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Target Current

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⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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M

Motor Starting Current

Inrush Estimator

Estimate full-load current (FLC) and transient peak starting current based on motor starter type (DOL, Star-Delta, Soft-Starter).

⚡ Output — Calculated Results

Full-Load (FLC)

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Starting Current

—

Rec. protection

—

⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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Standby Generator Sizing

Connected Load & Motor Starting

Size diesel standby power generators correctly, integrating connected load diversity profiles and motor startup power surges.

⚡ Output — Calculated Results

Required Load

—

Standard generator

—

Amps capacity

—

⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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Voltage Drop

Single/Three Phase

Verify that operational voltage drop along feeder cables does not exceed the standard 4% IEC regulatory boundary.

⚡ Output — Calculated Results

Voltage Drop

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Percentage Drop

—

IEC Status

—
⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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Short-Circuit Current

Prospective Fault

Estimate prospective short circuit current (Isc) downstream of your utility transformer to verify switchgear breaking capacity requirements.

⚡ Output — Calculated Results

Transformer FLC

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Fault Current

—

Breaking Capacity

—

⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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Earthing Conductor

IEC 60364 Sizing

Size minimum protective grounding conductor cross-sections to safely handle fault energy dissipation without thermal damage.

⚡ Output — Calculated Results

Min Ground CSA

—

Standard CSA

—

Terminations

—

⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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Busbar Sizing

Cross-Section Estimator

Obtain standard copper or aluminium flat rectangular busbar layout recommendations based on nominal switchboard current capacity.

⚡ Output — Calculated Results

Required Area

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Suggested Bar

—

Standoff Span

—

⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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Lighting Lumen Method

Fixture Count Estimator

Estimate total luminaire fixture count required to achieve targeted lighting lux parameters across indoor working spaces.

⚡ Output — Calculated Results

Fixtures Required

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Total Load

—

Load Current

—

⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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UPS Battery Sizing

Backup Autonomy

Determine target lead-acid or lithium battery battery bank AH rating and DC circuit breaker protection for standby UPS backup loads.

⚡ Output — Calculated Results

Required Capacity

—

Storage energy

—

DC Breaker Size

—

⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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Solar PV Sizing

Off-Grid Estimator

Size off-grid solar panels array peak rating, storage battery capacity, and hybrid solar power inverter rating based on load consumption.

⚡ Output — Calculated Results

Array Sizing

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Panels Required

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Inverter rating

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⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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MCB/MCCB/ACB Sizing

Circuit Breaker selector

Calculate design current and select appropriate nominal breaker rating, frame size (MCB, MCCB, ACB), and tripping curves.

⚡ Output — Calculated Results

Nominal rating

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Breaker Frame

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Tripping Curve

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⚡ Accessories & Technical Specs Click to expand

⚡ Ratings

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🛠️ Accessories

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🔍 Filters & Details

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